Year Percent 1950 1.54256 1955 1.89052 1960 2.36889 1965 2.72301 1970 3.00866 1975 3.19371 1980 3.34285 1985 3.55776 1990 3.91337 1995 4.00671 2000 4.00385 2005 4.06306 2010 4.09085 2015 4.13305 2020 4.24027 2025 4.34259 2030 4.17343 2035 4.04115 2040 4.0048 2045 4.0075 2050 4.05068 2055 4.22039 2060 4.65061 2065 5.27673 2070 6.01274 2075 6.83598 2080 7.7488 2085 8.76529 2090 9.88576 2095 11.10616 2100 12.41671